I do repeat 1000 times. The code I posted here: http://forum.btframework.com/index.php?topic=554.msg2912#msg2912 works perfect. Tested on about 20 PCs with different drivers. Check your code, check your drivers. Any way, I do repeat once again: I need more technical details (I told the same to your coworker), drivers, drivers version, enveronment, os version, dongle, model, target device and its model.